Abstract: According to one embodiment, a head actuator includes a first suspension assembly including a first support plate, a first wiring member with first wiring lines, and a first head, and a second suspension assembly including a second support plate, a second wiring member with second wiring lines, and a second head. The first wiring lines include at least four first read lines and at least four first write lines. The second wiring lines include at least four second read lines and at least four second write lines. At least two of the first read lines and at least two of the first write lines are arranged at a position offset to the second read lines and the second write lines in a width direction of the wiring member.

Abstract: Various embodiments concern a flexure comprising a base metal layer. The base metal layer can have a void between a first lateral side and a second lateral side. The flexure can further comprise a plurality of traces in an array. The plurality of traces can extend over the void and between the first and second lateral sides. The plurality of traces can comprise a pair of outer traces respectively located on lateral ends of the array and at least one inner trace between the pair of outer traces. The plurality of traces and the first and second lateral sides can be spaced relative to each other such that adjacent traces of the plurality of traces capacitively couple to each other and the pair of outer traces capacitively couple with each other through the first and second lateral sides.

Abstract: Jumper constructions for an integrated lead flexure for a disk drive head suspension include a conductive base layer, an insulating layer over the base layer, a plurality of traces arranged on the insulating layer, and an isolated conductor layer arranged under the insulating layer. The plurality of traces include a first trace and a second trace and the isolated conductor layer is electrically isolated from the conductive base layer and electrically connects the first and second traces.

Abstract: The problem of the present invention is to provide a circuit board comprising a shape retention unit capable of thinning while maintaining mechanical strength. The present invention solves the above-mentioned problem by providing a circuit board comprising a metal supporting substrate, a first insulating layer formed on the above-mentioned metal supporting substrate, and a wiring layer formed on the above-mentioned first insulating layer, wherein an open area is formed in the above-mentioned metal supporting substrate, and the circuit board comprises a shape retention unit having a second insulating layer contacting with the above-mentioned metal supporting substrate and a reinforcing layer formed on the above-mentioned second insulating layer, and bridging the above-mentioned metal supporting substrate divided by the above-mentioned open area.

Abstract: A slit is formed between two opposite side portions of a metal base made of an electrically conductive material. The slit penetrates the metal base thicknesswise and extends longitudinally relative to the metal base. An insulating layer is formed on the metal base. A first conductor is formed within the slit. The first conductor extends longitudinally relative to the metal base along the slit. A second conductor is formed on the insulating layer. The second conductor faces the first conductor across the insulating layer. The second conductor extends longitudinally relative to the metal base along the first conductor. The metal base and the first conductor consist of a common base material, such as a stainless-steel plate. The first conductor is formed by etching the base material.

Abstract: In one embodiment, a magnetic head includes a write pole; a write coil adapted for causing the write pole to emit a magnetic field upon excitation of the write coil; and a first capacitor and a second capacitor electrically connected in parallel with the write coil, each capacitor including a planar bottom plate, a top plate positioned parallel to the bottom plate, and at least one dielectric layer positioned between the top plate and the bottom plate, wherein a parasitic capacitance between the bottom plate of each capacitor and a substrate positioned below the bottom plate exists during writing operations of the magnetic head, and wherein the parasitic capacitances of the capacitors are about balanced.

Abstract: A disk drive is disclosed comprising a disk, a head actuated over the disk, a preamp, and an interconnect for coupling the head to the preamp. The interconnect comprises a first transmission line stacked with a second transmission line, and a dielectric between the first transmission line and second transmission line. The transmission lines form an approximation of at least one inductor/capacitor ladder network and an approximation of at least one inductor/capacitor lattice network. The lattice network comprises a first leg and a second leg, and a cross-over hub for interconnecting the first leg and the second leg.

Abstract: A suspension board with circuit includes a circuit board including a metal supporting board, an insulating layer formed on the metal supporting board, a conductive layer formed on the insulating layer, and an optical waveguide disposed on the circuit board. The optical waveguide includes an under clad layer, a core layer formed on the under clad layer, and an over clad layer formed on the core layer and included in the core layer when projected in the thickness direction of the core layer. The optical waveguide is provided with a positioning portion to position the optical waveguide and a near-field light generating unit for generating near-field light by a light emitted from the optical waveguide, and a protective layer to cover the positioning portion.

Abstract: A disk drive comprising a disk, and a head actuated over the disk, the head comprising a read element and a write element. The disk drive further comprises a preamp and an interconnect comprising a first transmission line and a second transmission line coupling the head to the preamp. A compensation network is disclosed operable to compensate for an impedance discontinuity in the first and second transmission lines, the compensation network comprising a first trace and a second trace connected in parallel with the first and second transmission lines, wherein a shape of the first and second traces varies to form at least a first capacitor.

Abstract: Jumper constructions for an integrated lead flexure for a disk drive head suspension include a conductive base layer, an insulating layer over the base layer, a plurality of traces arranged on the insulating layer, and an isolated conductor layer arranged under the insulating layer. The plurality of traces include a first trace and a second trace and the isolated conductor layer is electrically isolated from the conductive base layer and electrically connects the first and second traces.

Abstract: A first insulating layer is formed on a suspension body and a wiring trace is formed on the first insulating layer. In addition, a ground trace is formed on the first insulating layer so as to extend along the wiring trace on one side of the wiring trace with a spacing therebetween. A second insulating layer is formed on the first insulating layer to cover the wiring trace and the ground trace. On the second insulating layer, a wiring trace is formed at a position above the wiring trace. A third insulating layer is formed on the second insulating layer to cover the wiring trace. The width of the wiring trace is set larger than the width of the wiring trace. At least a partial region of the ground trace and at least a partial region of the wiring trace are opposite to each other with part of the second insulating layer sandwiched therebetween.

Abstract: An integrated conductor/suspension structure for supporting and electrically connecting a write/read head in a hard disk drive and methods of making the conductor/suspension structure are provided. The integrated conductor/suspension structure may allow for an increased characteristic-impedance range, greater interference shielding and a reduction of signal loss that is contributed by a lossy conductive substrate. The suspension structure includes apertures formed therein that result in a reduction in the lossy material and its effect on the electrical signals. In addition, the conductor/suspension structure of the present invention provides shielding to reduce the interference from external electric fields.

Abstract: A disk pack, comprising at least one hard disk, is rotatably mounted to a housing. The disk pack defines an axis of rotation and a radial direction relative to the axis. At least one actuator mounted to the housing is coupled with a suspension and is movable relative to the disk pack. A slider, comprising a slider body and a head configured to read data from and write data to at least one hard disk, is coupled with the suspension. A first suspension electrical interconnect is configured to electrically couple a first signal conducting pathway with the slider and with a first non-terminated signal pathway. A second suspension electrical interconnect is configured to electrically couple a second signal conducting pathway with the slider and with a second non-terminated signal pathway. The length of the second non-terminated signal pathway is selected to achieve a desired impedance level.

Abstract: Disclosed herein are embodiments directed to a head gimbal assembly including a novel suspension assembly that includes a flexure tail with a first plurality of apertures in its structural layer. Each of the first plurality of apertures underlies a first trace but not a second trace. Each of a second plurality of apertures in the structural layer underlies a second trace but not the first trace. Each of the first plurality of apertures includes a corresponding region of maximum width, and each of the second plurality of apertures includes a corresponding region of maximum width, as measured in the width direction. None of the corresponding regions of maximum width of the first plurality of apertures is disposed in an overlapping position along the long axis as any of the corresponding regions of maximum width of the second plurality of apertures.

Abstract: A slit is formed between two opposite side portions of a metal base made of an electrically conductive material. The slit penetrates the metal base thicknesswise and extends longitudinally relative to the metal base. An insulating layer is formed on the metal base. A first conductor is formed within the slit. The first conductor extends longitudinally relative to the metal base along the slit. A second conductor is formed on the insulating layer. The second conductor faces the first conductor across the insulating layer. The second conductor extends longitudinally relative to the metal base along the first conductor. The metal base and the first conductor consist of a common base material, such as a stainless-steel plate. The first conductor is formed by etching the base material.

Abstract: An integrated lead suspension (ILS) in a magnetic recording disk drive has the transmission line portion of the ILS between the flex cable and the gimbal formed of multiple interconnected segments, each with its own characteristic impedance. At the interface between any two segments there is a change in the widths of the electrically conductive traces of the transmission line. The change in impedance of a fixed-length segment is a function of the change in its trace width. The number of segments and their characteristic impedance values are selected to produce the largest frequency bandwidth with a substantially flat group delay from the write driver to the write head.

Abstract: A novel suspension assembly includes a flexure tail with a first plurality of apertures in its structural layer. Each of the first plurality of apertures underlies a first trace but not a second trace. Each of a second plurality of apertures in the structural layer underlies a second trace but not the first trace. Each of the first plurality of apertures includes a corresponding region of maximum width, and each of the second plurality of apertures includes a corresponding region of maximum width, as measured in the width direction. None of the corresponding regions of maximum width of the first plurality of apertures is disposed in an overlapping position along the long axis as any of the corresponding regions of maximum width of the second plurality of apertures.

Abstract: A flexure comprises a metal base, an insulating layer, and first and second conductors. First and second openings are formed so as to extend longitudinally relative to the metal base. These openings are formed at predetermined intervals longitudinally relative to the metal base. The metal base comprises ground regions continuous in a longitudinal direction thereof, ladder portions extending transversely relative to the metal base, and band-like portions formed between the openings. The band-like portions are located so as to overlap a gap between the conductors when the metal base is viewed vertically thicknesswise from above. The band-like portions extend longitudinally relative to the metal base along the conductors. Junctions are formed between the ground regions and band-like portions.

Abstract: An integrated lead head suspension flexure includes a mounting region, a gimbal extending distally from the mounting region and having bond pads, and a tail extending proximally from the mounting region and having terminal pads. First trace sections having a first structural configuration, such as interleaved traces, are electrically connected to the terminal pads and extend across the tail and mounting region. Second trace sections having a second structural configuration different than the first structural configuration, such as ground plane traces, are electrically connected to the bond pads and extend across the gimbal. Transition structures electrically connect the first trace sections to the second trace sections. The first and second trace sections impedance match the different impedances at the bond pads and terminal pads.

Abstract: A hard disk drive apparatus includes a magnetic head having a write head to record data on a disk and a read head to read the data recorded on the disk, at least one actuator arm on which the magnetic head is mounted, a voice coil motor to rotate the at least one actuator arm across the disk, a printed circuit board electrically connected to the write head, the read head, and the voice coil motor, and a flexible printed circuit having at least one write trace to electrically connect the write head and the printed circuit board, at least one read trace to electrically connect the read head and the printed circuit board, and a voice coil motor trace to electrically connect the voice coil motor and the printed circuit board. In the hard disk drive, the write trace is arranged between the read trace and the voice coil motor trace.

Abstract: An integrated lead flexure includes traces with windowed or reduced width portions. The flexure includes a metal base layer with a plurality of apertures, an insulating layer on the metal base layer, and one or more conductive traces formed on the insulating layer and extending over the metal base layer and the plurality of apertures. Backed portions of the one or more conductive traces that extend over the metal base layer have a first width, and unbacked portions of the one or more conductive traces that extend over the plurality of apertures have a second width that is less than the first width.

Abstract: This application discloses a hard disk drive, a head stack assembly, and a printed circuit board configured to include impedance patches on the flex ground plane, the flex power plane, the printed circuit ground plane and/or the printed circuit power plane over or under a connector site in the disk base that conveys access read and write differential signals for the sliders' access of rotating disk surfaces. These impedance patches minimize impedance discontinuities in the read and/or write differential signals through the connector site, which may improve the ability of the hard disk drive to transmit these signals at higher frequencies.

Abstract: A system comprises a plurality of storage drives coupled to logic. The logic implements a noise-reducing feature selected from a group consisting of a first feature that limits system performance based on a level of ambient noise, a second feature that staggers access transactions among said storage drives, a third feature that staggers spin up among the storage drives, a fourth feature that at least partially cancels noise generated by the system, a fifth feature that limits fan speed, and combinations thereof.

Abstract: An integrated lead flexure having a spring metal layer, a dielectric insulating layer on a side of the spring metal layer, a conductor layer on the side of the insulating layer opposite the spring metal layer and a coverlay on the side of the conductor layer opposite the insulating layer. The flexure further includes base region, a gimbal region extending from the base region, and a tail region extending from the base region opposite the gimbal region. The conductor layer includes terminal pads at the tail region and head bond pads at the gimbal region. Traces in the conductor layer extend between the terminal pads and the head bond pads across the tail, base and gimbal regions. One or more spring metal windows in the spring metal layer at the tail region are adjacent to substantial portions of at least some of the traces. One or more coverlay windows in the coverlay at the tail region are adjacent to substantial portions of the tail region spring metal windows.

Abstract: A flexible mounting slider with anti-static structure includes a slider body, an anti-static structure and a lead layer. The slider body includes an ABS, a slider back surface opposite to the ABS and a trailing edge connected with the ABS and the slider back surface. The trailing edge forms a plurality of slider pads thereon. The anti-static structure is provided on the slider back surface, which includes an insulation plate formed on the slider back surface, an anti-static plate formed on the insulation plate and a grounding element. In the invention, the anti-static plate comprises an insulation layer and an anti-static layer. The grounding element is electrically contacting with the anti-static layer of the anti-static plate and the slider back surface simultaneously. The lead layer is sandwiched between the insulation plate and the insulation layer of the anti-static plate and electrically connected with the slider pads of the slider body.

Abstract: A first insulating layer is formed on a suspension body, and a write wiring trace and a read wiring trace are formed on the first insulating layer. A second insulating layer is formed on the first insulating layer so as to cover the wiring traces. A write wiring trace and a read wiring trace are formed on the second insulating layer. A third insulating layer is formed on the second insulating layer so as to cover the wiring traces. The width of the wiring trace is larger than the width of the wiring trace, and the width of the wiring trace is larger than the width of the wiring trace.

Abstract: An integrated lead suspension (ILS) has a constrained layer damper (CLD) that attenuates vibration of the ILS. The CLD is applied over an already assembled ILS such that the CLD is applied to the cover layer. The CLD encapsulates the underlying conductors and the cover layer. The damping layer is formed on the cover layer. The width of damping layer is substantially equal to the width of cover layer as it extends over the conductors. The constraining layer extends laterally beyond the width of the damping and cover layers and down to the dielectric layer, which resides on a base layer. The constraining layer has a lateral width equal to that of the dielectric layer.

Abstract: A disk drive suspension interconnect, and method therefor. The interconnect has a metal grounding layer, a metal conductive layer and an insulative layer between the metal grounding layer and the conductive metal layer. A circuit component such as a slider is electrically connected to the conductive layer along a grounding path from the circuit component and the conductive layer to the metal grounding layer through an aperture in the insulative layer. For improved electrical connection a tie layer is provided through the insulative layer onto the grounding layer in bonding relation with the ground layer. A conductor is deposited onto both the conductive metal layer and the tie layer in conductive metal layer and tie layer bonding relation, and the circuit component is thus bonded to the grounding layer by the conductor.

Abstract: An integrated lead flexure for a disk drive head suspension of the type having a plurality of stacked leads disposed on separate layers, the plurality of stacked leads extending between terminal connector pads and head connector pads, comprising stacked lead pairs having opposing and regularly alternating wider and narrower portions, respectively.

Abstract: A suspension having a magnetic head assembly 1 mounted thereon is provided, wherein the magnetic head assembly comprises: a write head 1-2; a read head 1-1; and a resistive heating element 1-3 for controlling the flying heights of the magnetic heads, wherein the wires HTx and GTx for the resistive heating element is disposed such that they sandwich the wires RxX and RxY for the read head. The wires for the resistive heating element may be disposed between the wires for the write head and the wires for the read head. Furthermore, the waveform of the current or voltage to the resistive heating element has a time constant of 1 ?sec or more, the resistive heating element having wires disposed near the wires of the read head.

Abstract: A magnetic head slider supporting apparatus comprises: a suspension flexibly supporting a slider; and a flexible wiring board. The suspension incorporates a load beam. The flexible wiring board is disposed along the load beam. The flexible wiring board includes: first and second lines for connecting a write element that the slider includes to a read/write processing circuit; and third and fourth lines for connecting a read element that the slider includes to the read/write processing circuit. The flexible wiring board further includes two conductors for generating two parasitic capacitances for reducing potential differences created between the third and fourth lines due to write signals transmitted through the first and second lines.

Abstract: A storage apparatus and a magnetic head driving device includes a recording/reproducing head including a write element and a magnetoresistive element, a driving circuit for driving the write element and the magnetoresistive element, and write wires and read wires which connect the recording/reproducing head to the driving circuit. The write wires and the read wires are disposed in parallel in at least a portion between the recording/reproducing head and the driving circuit. At a location between the recording/reproducing head and the driving circuit, either of the write wires and the read wires are disposed so that a polarity of the either of the write wires and the read wires is reversed with respect to a polarity of the other of the write wires and the read wires.

Abstract: A symmetrical read element circuit for reducing electrical and magnetic noise using signal processing, such as a differential preamplifier. The circuits are symmetrically created on both sides of the read element so that the noise is balanced on both sides of the read element to allow substantial noise reduction by the signal processing.

Abstract: An electrical lead suspension (ELS) having partitioned air slots. The ELS includes a laminate. A first plurality of signal traces and a second plurality of traces are in a first formed layer of the laminate. The second plurality of traces may be signal traces or power traces. The laminate has a dielectric layer between the first formed layer and a second formed layer. A plurality of partitioned air slots is in the second formed layer of the laminate. The portion of the ELS having a plurality of partitioned air slots supporting the at least the first plurality of signal traces and the portion of the ELS having a second plurality of partitioned air slots or patterns supporting the second plurality of traces. The supporting of the first plurality of signal traces separate from the second plurality of traces reduces write-to-read cross talk and signal loss.

Abstract: An apparatus and method for reducing solder pad size in an electrical lead suspension (ELS) to decrease signal path capacitive discontinuities. The method provides a base-metal layer for the ELS. A dielectric layer above the base-metal layer is also provided. A signal conductive layer is provided above dielectric layer. The signal conductive layer carries at least one solder pad portion, wherein both a size of the solder pad portion and an amount of solder applied to the solder pad portion are reduced such that the solder pad to a ground, and solder on the solder pad to adjacent solder on adjacent pads, capacitance are reduced providing low signal reflection losses and a decrease in cross-talk.

Abstract: A suspension having a magnetic head assembly 1 mounted thereon is provided, wherein the magnetic head assembly comprises: a write head 1-2; a read head 1-1; and a resistive heating element 1-3 for controlling the flying heights of the magnetic heads, wherein the wires HTx and GTx for the resistive heating element is disposed such that they sandwich the wires RxX and RxY for the read head. The wires for the resistive heating element may be disposed between the wires for the write head and the wires for the read head. Furthermore, the waveform of the current or voltage to the resistive heating element has a time constant of 1 ?sec or more, the resistive heating element having wires disposed near the wires of the read head.

Abstract: Embodiments of the invention provide a magnetic disk drive which has improved electrical properties owing to a reduction in the loss of transmission line, improved vibration properties owing to a reduction in the stiffness of wiring around the head, and a flat impedance in the transmission line. In one embodiment, a magnetic disk drive comprises a suspension; a magnetic head coupled with the suspension and configured to write and read information to and from a magnetic recording medium; and a transmission line disposed on the suspension to transmit writing and reading information to and from the magnetic head. The transmission line includes a writing line and a reading line, a lower conductor disposed underneath the writing line and the reading line, and an insulating layer interposed between the lower conductor and the writing and reading lines.

Abstract: A suspension for use in a disk drive is disclosed. The suspension has a hinge and load beam which are separately formed and subsequently joined together. The load beam is formed from a material which has improved damping characteristics. The load beam additionally has ribs constructed in order to balance the mass of the suspension about the torsional rotation axis. The location of the torsional rotation axis can be designed to intersect the head gimbal pivot point.

Abstract: A system for reducing signal crosstalk in a flexible trace interconnect array includes a flexible dielectric material base, and a plurality of conductors longitudinally arranged as pairs in a signal layer array on the base. At least one of the pairs of conductors comprises a twisted pair.

Abstract: A symmetrical read element circuit for reducing electrical and magnetic noise using signal processing, such as a differential preamplifier. The circuits are symmetrically created on both sides of the read element so that the noise is balanced on both leads of the sensor element allowing substantial noise reduction by the signal processing. That is, the present invention provides symmetrical leads and pads designed for equal noise pickup, and for cancellation of the balanced noise.

Abstract: Methods and devices are described that provide improved electromagnetic interference (EMI) protection for suspension assemblies. In one embodiment, a ground line is provided among the traces that are used in the suspension. Alternatively, a top ground plane is provided on top of the conductive traces with an interposed insulative layer. The ground line and/or the top ground plane provide EMI protection for read and write signals traveling through the traces (e.g., read and write traces) of the suspension assembly. The ground line and/or the top ground plane reduce the interaction between the read and the write traces, thus minimizing cross talk.

Abstract: A wiring portion has first and second write conductors, first and second read conductors, and an insulating layer. The first write conductor, first and second read conductors, and second write conductor are arranged three-dimensionally at different height levels in the thickness direction of the insulating layer, in a cross section extending in the width direction of the wiring portion. The distance from the first write conductor to the first read conductor is equal to the distance from the first write conductor to the second read conductor. The distance from the second write conductor to the first read conductor is equal to the distance from the second write conductor to the second read conductor.

Abstract: A suspension having a magnetic head assembly 1 mounted thereon is provided, wherein the magnetic head assembly comprises: a write head 1-2; a read head 1-1; and a resistive heating element 1-3 for controlling the flying heights of the magnetic heads, wherein the wires HTx and GTx for the resistive heating element is disposed such that they sandwich the wires RxX and RxY for the read head. The wires for the resistive heating element may be disposed between the wires for the write head and the wires for the read head. Furthermore, the waveform of the current or voltage to the resistive heating element has a time constant of 1 ?sec or more, the resistive heating element having wires disposed near the wires of the read head.

Abstract: Magnetic disk apparatus includes an electric wiring capable of satisfying an electric condition under which high frequency recording higher than or equal to 200 MHz, a magnetic head having at least a recording device to a magnetic recording medium, and also the electric wiring corresponding to a recording current supplying device to this magnetic head are formed on a suspension member for mechanically suspending the magnetic head, the recording current being supplied to a magnetic head recording device by employing such electric wiring, the characteristic impedance of which is higher than a maximum impedance of the magnetic head recording device.

Abstract: A disk drive suspension and method has a metal load beam and an electrical interconnect assembly. The interconnect assembly has an insulative layer, a read pair of forward and return path conductive traces, a write pair of forward and return path conductive traces that are supported by the insulative layer, preferably in offset relation across the insulative layer, and a metal layer for grounding and mounted on the insulative plastic layer in fixed spaced relation to the conductive traces to be between the interconnect assembly and the load beam. The metal layer shields the conductive traces from variations in impedance occasioned by varying distances between said electrical interconnect and said load beam.

Abstract: A wired flexure comprises a metallic substrate, a polyimide layer formed on the metallic substrate, and read conductors and write conductors formed on the polyimide layer. The polyimide layer has a thick-walled portion and a thin-walled portion that are different in thickness. The read and write conductors extend covering the thick- and thin-walled portions. In order to obtain a desired impedance, the width of the conductors in the thin-walled portion is smaller than that of the conductors in the thick-walled portion.

Abstract: Magnetic disk apparatus includes an electric wiring capable of satisfying an electric condition under which high frequency recording higher than or equal to 200 MHz, a magnetic head having at least a recording device to a magnetic recording medium, and also the electric wiring corresponding to a recording current supplying device to this magnetic head are formed on a suspension member for mechanically suspending the magnetic head, the recording current being supplied to a magnetic head recording device by employing such electric wiring, the characteristic impedance of which is higher than a maximum impedance of the magnetic head recording device.

Abstract: A wired flexure comprises a substrate formed of an electrically conductive material, a read wire provided on the substrate so as to extend along the substrate, a write wire provided on the substrate so as to extend along the read wire, a slit formed between the read and write wires, etc. The slit extends along the read and write wires and divides the substrate between a first portion on the read wire side and a second portion on the write wire side. The slit is situated nearer to the read wire than to the write wire.

Abstract: A method of adjusting the common mode impedance while enabling maintenance of the differential mode impedance of a pair of traces located with respect to a ground plane formed by a load beam or trace assembly of a disk drive head suspension. The method includes forming a ground plane having apertures with isolated conductive islands in the apertures for setting a desired common mode impedance. The method includes a cut and try approach using sample coupons to adjust the ratio of backed area to island area to adjust the common mode impedance while maintaining the differential mode impedance by maintaining the ratio of unbacked area to the sum of the backed and island areas.

Abstract: Apparatus and method of adjusting the common mode impedance while enabling maintenance of the differential mode impedance of a pair of traces located with respect to a ground plane formed by a load beam or trace assembly of a disk drive head suspension. The ground plane has apertures with isolated conductive islands in the apertures for setting a desired common mode impedance. The method includes a cut and try approach using sample coupons to adjust the ratio of backed area to island area to adjust the common mode impedance while maintaining the differential mode impedance by maintaining the ratio of unbacked area to the sum of the backed and island areas.